Complete submergence of plants prevents direct O(2) and CO(2) exchange with air. Underwater photosynthesis can result in marked diurnal changes in O(2) supply to submerged plants. Dynamics in pO(2) had not been measured directly for submerged rice (Oryza sativa), but in an earlier study, radial O(2) loss from roots showed an initial peak following shoot illumination. O(2) dynamics in shoots and...

Spartina alterniflora, a perennial grass with C(4)-photosynthesis, shows great invading potential in the coastal ecosystems in the east of China. We compared trace gas emissions from S. alterniflora with those from a native C(3) plant, Phragmites australis, by establishing brackish marsh mesocosms to experimentally assess the effects of plant species (S. alterniflora vs. P. australis), flooding...

Living stromatolites growing in a hot spring in Yellowstone National Park are composed of silica-encrusted cyanobacterial mats. Two cyanobacterial mat types grow on the stromatolite surfaces and are preserved as two distinct lithofacies. One mat is present when the stromatolites are submerged or at the water-atmosphere interface and the other when stromatolites protrude from the hot spring. The...

The amphibious leafless sedge Eleocharis vivipara develops C 4 -like traits as well as Kranz anatomy under terrestrial conditions, but it develops C 3 -like traits without Kranz anatomy under submerged conditions. When submerged plants are exposed to aerial conditions, they rapidly produce new photosynthetic tissues with C 4 -like traits. In this study, experiments were performed to determine w...

The identification and characterization of barriers to river continuity are essential for the preparation an inventory hydraulic infrastructure. To this end, it is necessary define main identifying characterizing elements infrastructures descriptors ecological continuity, with information that can characterize them from point view their impact on watercourse. Several authors have defined decisi...

N.sitophila was grown under controlled conditions of solid state and submerged fermentation on Sago hampas. The optimum conditions of protein enrichment previously established for sugar beet pulp was used for this study. Under this condition the protein content of Sago hampas under solid state increased from 1.4 to 14.45% (W/W) whereas for Sago hampas and Sago starch, the protein content under ...

Invasion by free-floating species, such as Eichhornia crassipes, is one of the most critical threats to the biodiversity and sustainability of wetland ecosystems, where all plants experience spatial heterogeneity in substrate nutrients. However, few studies have focused on the effects of free-floating invaders on the capacity of submerged plants to utilize substrate nutrients. A 10-week greenho...

Abstract Climate change has caused the inefficient operation of a significant number old weirs to pass large discharges. Therefore, this study aims increase discharge capacity labyrinth weir. A new approach was proposed by modifying weir structure. The data obtained from quarter-round crest and different sidewall angles ranging 8 35°. conventional used for comparison. results showed that percen...

Abstract Weirs are one of the most common hydraulic structures used in water engineering projects. In this research, a group method data handling (GMDH) was developed to estimate energy dissipation flow passing over labyrinth weirs with triangular and trapezoidal plans. To compare performance model other types soft computing models, multilayer perceptron neural network (MLPNN) developed. The di...

In this study, we have investigated variations in the potential of floating and submerged leaves of longleaf pondweed (Potamogeton nodosus) to withstand silver ion (Ag+)-toxicity. Both floating and submerged leaves changed clear colorless AgNO3 solutions to colloidal brown in the presence of light. Transmission electron microscopy revealed the presence of distinct crystalline Ag-nanoparticles (...